How to get array of objects by arrays in javascript

Question

For the array object and arrays,

return the array of objects only when

same value and dont have any model that matches arrayitem
same value and has same model whether matches or not in arrayitem

return [] when

same value and has atleast one model exists in the arrayitem

My attempts

var arrayitem =["swatch", "titan"];

var arrobj1=[
  {id:1, name: "xys", model:"car", value: 200},
  {id:2, name: "abc", model:"titan", value: 200},
  {id:3, name: "tex", model:"plane", value: 300},
]
/*
 Expected Output:
 value same and model exists in arrays
 []
*/

var arrobj2=[
  {id:1, name: "xys", model:"titan", value: 200},
  {id:2, name: "abc", model:"plane", value: 300},
  {id:3, name: "tes", model:"plane", value: 300},
]

/*
Expected Output:
// both value and model same
[
  {id:2, name: "abc", model:"plane", value: 300},
  {id:3, name: "tes", model:"plane", value: 300}
]
*/

var arrobj3=[
  {id:1, name: "xys", model:"car", value: 200},
  {id:2, name: "abc", model:"titan", value: 300},
  {id:3, name: "tes", model:"swatch", value: 300},
]

/* Expected Output
//same value and alteast one matches the arrays
[]
*/


const getArr = arrobj => arrobj
      .map((obj, i) => {
        return arrobj1.find((element, index) => {
          if (i !== index && element.value === obj.value) {
            if(element.model !== obj.model && 
              (!arrayitem.includes(element.model) && !arrayitem.includes(obj.model))){
              return obj;
            } if(element.model === obj.model) {
              return obj;
            }
          }
        })
      })
      .filter(x => x);

console.log(1, getArr(arrobj1))
console.log(2, getArr(arrobj2))
console.log(3, getArr(arrobj3))

What do you mean by value same? Value same of what? Please make your question more clear! — Som Shekhar Mukherjee
– Som Shekhar Mukherjee, Commented Apr 21, 2022 at 9:37
I made you a snippet - it seems you get the expected outputs — mplungjan
– mplungjan, Commented Apr 21, 2022 at 9:39
@mplungjan thanks but is there any other way to do using javascript — code123
– code123, Commented Apr 21, 2022 at 11:52

Peter Seliger · Accepted Answer · 2022-04-22 08:02:08Z

An approach was to break down the code into single tasks/functions which could be combined in order to cover the OP's scenario/requests.

Thus one would write two configurable filtering functions where one could pass each the property-name/key in order to compare the correct property values with the values from an additionally passed value-list.

One function returns all items which do match the value-list.
The other one returns all items which do not match the value-list.

In order to cut down costs (nested iterations), one would implement a helper function which does create a map (single iteration) from the value-list where this map gets utilized for inexpensive value lookups by both filtering functions.

There is one task left, the creation of (a) list(s) of same items, where sameness is assured/defined by property-value equality for every property-name/key from a set of specified keys.

Thus one again would write a configurable functions where one in addition to an item list does pass a key configuration to.

function getValueMapFromList(list) {
  return new Map(list.map(value => [value, value]));
}

function getPropertyValueMatchingItemsByKey(
  targetList,
  valueList,
  key,
) {
  const lookup = getValueMapFromList(valueList);
  return targetList.filter(item => lookup.has(item[key]));
}
function getPropertyValueNonMatchingItemsByKey(
  targetList,
  valueList,
  key,
) {
  const lookup = getValueMapFromList(valueList);
  return targetList.filter(item => !lookup.has(item[key]));
}

function getItemsOfSamePropertyValuesByKeys(
  targetList = [],
  keyConfig = {},
) {
  let { primaryKey = null, keyList = [] } = keyConfig;

  if (Array.isArray(keyConfig)) {
    keyList = keyConfig;
  } else {
    keyList.unshift(primaryKey);
  }
  let sameValueItems = targetList
    .filter((targetItem, idx, arr) => [
        ...arr.slice(0, idx),
        ...arr.slice(idx + 1),
      ]
      .some(siblingItem => keyList
        .every(key =>
          siblingItem[key] === targetItem[key]
        )
      )
    );
  if (primaryKey && (typeof primaryKey === 'string')) {
    // an available primary key triggers the grouping
    // of sub item-lists by this key which results in
    // an array of grouped arrays (the very sub items).
    sameValueItems = Object.values(
      sameValueItems.reduce((group, item) => {

        (group[item[primaryKey]] ??= []).push(item)

        return group;
      }, Object.create(null))
    );
  }
  return sameValueItems;
}
const listOfPropertyValues = ["swatch", "titan"];

const itemList_1 = [
  { id: 1, name: "xys", model: "car", value: 200 },
  { id: 2, name: "abc", model: "titan", value: 200 },
  { id: 3, name: "tex", model: "plane", value: 300 },
];
const itemList_2 = [
  { id:1, name: "xys", model: "titan", value: 200 },
  { id:2, name: "abc", model: "plane", value: 300 },
  { id:3, name: "tes", model: "plane", value: 300 },
];
const itemList_3 = [
  { id:1, name: "xys", model: "car", value: 200 },
  { id:2, name: "abc", model: "titan", value: 300 },
  { id:3, name: "tes", model: "swatch", value: 300 },
  { id:4, name: "xys", model: "car", value: 200 },
  { id:5, name: "abc", model: "titan", value: 300 },
];
// ... return the array of objects only when ...

console.log("same values from models which do not match `arrayitem`");
console.log('...arrayitem...', listOfPropertyValues);
console.log(
  '...for `itemList_1`...',
  getItemsOfSamePropertyValuesByKeys(

    // items of non matching `model` values.
    getPropertyValueNonMatchingItemsByKey(
      itemList_1, listOfPropertyValues, 'model'
    ),
    // the key configuration
    //  - either a real config which returns a grouped array of arrays.
    // { primaryKey: 'model', keyList: ['value'] }
    //  - or a simple key list which returns a flat ungrouped array.
    ['model', 'value']
  )
);
console.log(
  '...for `itemList_2`...',
  getItemsOfSamePropertyValuesByKeys(

    // items of non matching `model` values.
    getPropertyValueNonMatchingItemsByKey(
      itemList_2, listOfPropertyValues, 'model'
    ),
    ['model', 'value'] // { primaryKey: 'model', keyList: ['value'] }
  )
);
console.log(
  '...for `itemList_3`...',
  getItemsOfSamePropertyValuesByKeys(

    // items of non matching `model` values.
    getPropertyValueNonMatchingItemsByKey(
      itemList_3, listOfPropertyValues, 'model'
    ),
    ['model', 'value'] // { primaryKey: 'model', keyList: ['value'] }
  )
);

console.log("same values from models regardless of matching `arrayitem`");
console.log('...arrayitem...', listOfPropertyValues);
console.log(
  '...for `itemList_1`...',
  getItemsOfSamePropertyValuesByKeys(
    itemList_1,
    { primaryKey: 'model', keyList: ['value'] } // ['model', 'value'] 
  )
);
console.log(
  '...for `itemList_2`...',
  getItemsOfSamePropertyValuesByKeys(
    itemList_2,
    { primaryKey: 'model', keyList: ['value'] } // ['model', 'value'] 
  )
);
console.log(
  '...for `itemList_3`...',
  getItemsOfSamePropertyValuesByKeys(
    itemList_3,
    { primaryKey: 'model', keyList: ['value'] } // ['model', 'value'] 
  )
);

console.log("same values from models which match `arrayitem`");
console.log('...arrayitem...', listOfPropertyValues);
console.log(
  '...for `itemList_1`...',
  getItemsOfSamePropertyValuesByKeys(

    // items of matching `model` values.
    getPropertyValueMatchingItemsByKey(
      itemList_1, listOfPropertyValues, 'model'
    ),
    { primaryKey: 'model', keyList: ['value'] } // ['model', 'value'] 
  )
);
console.log(
  '...for `itemList_2`...',
  getItemsOfSamePropertyValuesByKeys(

    // items of matching `model` values.
    getPropertyValueMatchingItemsByKey(
      itemList_2, listOfPropertyValues, 'model'
    ),
    { primaryKey: 'model', keyList: ['value'] } // ['model', 'value'] 
  )
);
console.log(
  '...for `itemList_3`...',
  getItemsOfSamePropertyValuesByKeys(

    // items of matching `model` values.
    getPropertyValueMatchingItemsByKey(
      itemList_3, listOfPropertyValues, 'model'
    ),
    { primaryKey: 'model', keyList: ['value'] } // ['model', 'value'] 
  )
);

.as-console-wrapper { min-height: 100%!important; top: 0; }

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